The Unarchiver is a much more capable replacement for "BOMArchiveHelper.app", the built-in archive unpacker program in Mac OS X. The Unarchiver is designed to handle many more formats than BOMArchiveHelper, and to better fit in with the design of the Finder. It can also handle filenames in foreign character sets, created with non-English versions of other operating systems.

@eliezer - Unarchiving .exe files isn't useless at allâ¦ While this is a lot less common nowadays, you still see some self-extracting zip filesâ¦Â That is, they're windows executables that just automatically extract the zip within. Inside the archive could be any number of things that a Mac user might want to get at. The unzip utility built into OS X actually supports these as well (unzip from command line, don't think BOMArchiveHelper does).

Recent 2.0 betas (builds and code) are on the google code site. Before, I'd have random errors on newer stuffit/sit and rars typically done on windows or with passwords. So far, no problems thus far and I enjoy the speed jump from stuffit.

The Unarchiver has its idiosyncrasies. It's snappy and light, however it doesn't support some of the formats it suggests. Rather strange is the fact that it seems to support unarchiving .exe files, which is obviously a tad useless (when it tried to expand one it gave errors). Also, .bin, .sit, and .sitx are unsupported although appear to be feasible. Nevertheless, it is useful for everyday usage.